1966 Land Rover Engine question

I get about 15 mpg with my 7:1 compression inline 4. I was looking around and Turner sells an 8:1 head for about 800 bucks. I was wondering if this would save me money in the long run? I know it would give me a bit more power.

Are there any other mods I could do to make my 1966 engine run a bit more efficiently, its only a 2.25 liter engine and the car is not a very heavy car.

This Rover is a really fun car to own but with gas getting so expensive I’ve been driving my Honda more and letting the Rover sit in the garage. It only gets to play about 100 miles a week, I would like to drive it more but the gas cost is about 1400 more per year (2000 a year for honda, 3400 for rover) than my honda. YIKES!

Bumping compression may help a bit, but the return on mpg probably isn’t worth the $800 investment and the added time to install it.
Instead, spend the $800 on a weber carb and spend your time getting it tuned just right.
You could probably break 20 mpg, but don’t expect much more. This car was built with very old technology that just isn’t capable of giving you high mpgs.

There are several engine mods available for the 2.5 engine all of which will enhance performance but none of which will dramatically improve your fuel consumption.

The head upgrade is a good perofrmance improver but won’t yield best results without a cam, inlet manifold, carb and exhaust upgrade. If everything is in generally good order I’d look at an overdrive upgrade first. The 2.5 has masses of torque but redlines at about 60 mph, an overdrive will certainly help with economy and highway driveability.

Other than that, I’d just use the Honda for any serious travelling and just keep the LR for the fun stuff.

How is this thing geared and it is possible to change the differential gear ratio? If it is built for hill-climbing and you drive it on normal roads you might benefit from a gear change. A higher final drive ratio will also preserve the engine if you drive at highway speeds.

OTOH, that thing is about as aerodynamic as a shoe box so it will never approach the Honda for fuel mileage.

That period LR doesn’t have optional diff gear sets, it has a high / low transfer plus and the low stress engine is designed for mud plugging around hill farms not the highway, the gears you get are what are made and that’s it unless you want to spend some serious money.

Think VW camper performance and you get the picture. The engine upgrades will improve acceleration performance (the 9:1 comp ratio was designed to permit the use of African gasoline which was 1 grade up from kerosene) but you really need the cam, inlet, carb and exhaust upgrades to deliver any real benefit - I seem to remember the tailpipe being a piddling 1 inch in diameter and being very restrictive. But nothing you can do will increase top speed or significanly improve fuel consumption other than an overdrive unit.

Fairey ODs are available for about $1500.

I have a lot of hill to climb where I live. So keeping the torque at the wheels is useful. If its not worth getting the mileage bumped up I would at least like to make the car a bit more powerful. I rarely want to go 60mph in that car but it would be nice to do 55 on hills and have some power to spare. The car has a new weber carb (I need to tune it a bit more) and it has a K&N air filter, not the oil bath one that came with it. It also has a new muffler and it has no cat converter or anything to help reduce emissions. I think the engine is just really tired. Its 42 years old and it served 40,000 of its 50,000 miles doing off road training maneuvers in the military.

I would like some more info on the mods to the 2.25 engine. Whats the easiest place to start?

Thanks guys,


I had a Rover 88 (88 is the wheel base in inches) it was the safari looking Rover. very slow but real fun to drive off road. Never once thought of modifing anything just used it and had fun. These are not daily drivers

I don’t know anyone in the US, the mainstream tuners are UK, NZ or SA.

But you could start here at ACR automotive, they may have a US contact : http://www.automotivecomp.com/landrover_perf.html

Forget the cylinder head swap. Depending on the majority of your type of driving a camshaft change (cam profile to fit most of your driving) and some intake manifold and current cylinder head porting would help some, BUT this will be expensive and in the event a custom cam is not available your current cam could be reground. Cost effective? Probably not.

As the vehicle sits and doing the easy stuff, I would concentrate on some carburetor jet changes and altering the ignition timing. Try advancing the timing about 4 degrees, drive it for a little, and make sure there is no pre-ignition rattle. If there is no rattle, put a 100 miles on it and pull the spark plugs for inspection. If they look good then the extra advance should be fine and should generate a slightly noticeable amount of extra power and fuel economy.
Also make sure the vacuum advance on the distributor is good and the advance mechanism is not sticking due to age.

50k miles is not much but if there is some concern about it being tired due to its past then pull the plugs and run a compression test.